基于CODE GIM的震前电离层TEC异常分析

ANALYSIS BASED IN CODE GIM OF IONOSPHERIC TEC ANOMALY BEFORE EARTHQUAKE

利用CODE GIM数据分析了2008年5月12日汶川地震和2010年4月14日青海玉树地震震前电离层TEC变化。以震前10天TEC中位数为基准,1.5倍标准差为误差限值,并考虑相应时期的太阳和地磁活动水平(Dst指数和Kp指数),对震前电离层异常的分布进行了分析。结果表明,两次地震震前几天内都有TEC异常出现。

Pre-seismic ionospheric TEC anomalies of Wenchuan earthquake on May 12th 2008 and Yushu earthquake on April 14th 2010 were studied by using CODE GIM（Center for Orbit Determination in Europe,Grid Ionospheric Model） data.By considering the sun and geomagnetism activity levels（Dst index and Kp index）,the ionospheric anomalies were analyzed with median of TEC 10 days earlier as basic values and 1.5 fold standard deviation as error limit.The results show that TEC anomalies before both the earthquakes can be detected.